Hydraulic Spring Drive Apparatus

ABSTRACT

Hydraulic spring drive apparatus comprising: a rotatable cam shaft having fixed thereon a number of cams; a number of rocker arms, one following each cam, each pivotally attached at one end to a pressure bar and at another to an expansible, compressible connecting means in turn connected to a crank portion of a crank shaft. The cams, crank shaft, and expansible compressible connecting means are arranged so that a number of connecting means expand against the compression of one connecting means. The pressure bar is movable to position the rocker arms for a selected degree of connecting means compression.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. ProvisionalApplication No. 60/899,924 filed on Feb. 6, 2007, the contents of whichare incorporated herein fully by reference.

FIELD OF THE INVENTION

The present invention is related to the field of motors and morespecifically, a hydraulically driven spring drive motor.

SUMMARY OF THE INVENTION

According to the present invention, a hydraulic spring drive apparatusis provided whereby independent spring force for rotation iscontinuously delivered by a number of expansible, compressibleconnecting means operating so that at any given time, more connectingmeans are expanding than are being compressed.

As embodied in a presently preferred apparatus, a rotatable cam shafthas axially spaced along its length a number of cams fixed to the shaftfor rotation therewith. Each cam has an edge varying in distance from acenter of rotation of the cam between a maximum distance and minimumdistance. A number of rocker arms, one following each cam, are pivotallyattached, in a predetermined position, to the apparatus at one end andsupport at an opposite end expansible, compressible connecting means. Acrank shaft having an eccentric crank portion for connection with eachconnecting means is rotatably driven by rotation of the cam shaft andreciprocal movement of the connecting means. Each cam is shaped so thatthe maximum distance at its edge extends through a minor portion (about90°) of its 360° rotation and the minimum distance extends through alarger portion (about 135°) of rotation with a sharp rise from minimumto maximum distance and a gradual decline from maximum to minimumdistance as the cam rotates. The arrangement at the edge of the camsprovides compression of one connecting means opposed to expansion of aplurality of other connecting means. A hydraulic pump may be connectedto the cam shaft for rotation with the cam shaft to aid in the operationof a throttle system. The throttle system may be used to control therest position of the rocker arms by displacing a pressure bar connectedto a rocker arm riding on each cam. Adjustment of the rocker armcontrols the degree of compression and expansion of each connectingmeans.

DESCRIPTION OF THE DRAWING

FIG. 1 is a side sectional view of an apparatus of the present inventionwith portions removed for clarity.

FIG. 2 is an end view of the apparatus of FIG. 1, with portions removedfor clarity.

FIG. 3 is a section view of the power unit assembly shown in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIGS. 1 and 2, the present apparatus is contained in arectangular housing 4 which supports a crank shaft 6, a cam shaft 8, anda rocker arm assembly 10. A hydraulic pump 12 and throttle assembly 14are mounted on the housing.

The crank shaft 6 is mounted axially through an upper portion of thehousing 4 through forward bearing 16 and rearward bearing 18 andcomprises equally axially spaced eccentric crank portions 20 for eachcam and connecting means, there being eight in the presently preferredembodiment. Each crank portion 20 comprises a pair of axially offsetmembers and a cross piece 22 which rotates in a circle of a givendiameter Dcr about the axis of rotation 24 of the crank shaft.

The cam shaft 8 is supported on a forward bearing 26 and a rearwardbearing 28 and supports eight cams 30 in equally axially spacedrelationship along its length, one opposite each crank portion 20. Thecam shaft terminates forwardly in a pulley wheel 32 and rearwardly in aflywheel 34. The cam shaft may be journaled to support engagement withthe plurality of cams for rotation therewith.

The cams 30 are mounted in circumferentially offset relationship to eachother so that each succeeding cam is offset from its rearwardly adjacentcam by 360° divided by the number of cams, or 45°. Similarly, each crankportion 20 is offset from its rearwardly adjacent crank portion by 45°so that, as shown in FIG. 2, a cam denominated 180 will be oppositelyconnected to a crank portion having its 180 portion engaging a rockerarm. A cam advanced 45° in the direction of arrow 36 is oppositelyconnected to a crank portion 225, and so forth. A timing gear 38 engagesgears 40, 42 on the crank shaft and cam shaft, respectively, to maintainthe cams and crank portion in the above-described predeterminedrelationship.

Each cam 30 is of the same modified disk shape having modified edgesurface 41 as shown in FIG. 2. Each cam may be divided into eightsectors, 0-360. The edge surface of sectors comprising angles 135-225are at a minimum distance from the axis 44 of rotation of the cams.Sectors 270 and 225 comprises a rate of 90° and the edge 41 of cam 30,is curved slightly outwardly. From 270° the edge continues at a maximumdistance from axis to sector 0, along which it describes a circle of adiameter approximately Dcr, From sector 0, the cam gradually returns toa minimum distance in the vicinity of sector 90.

With reference to FIG. 2, the rocker arm assembly 10 comprises anaxially elongated pressure bar 46 supported through three axiallyspaced, upwardly extending rod portions 48-52 (FIG. 2). The rod portions48, 50, 52 are slidably fitted into tube portions 49, 51, 53 in thehousing 4. Eight rocker arms 54 are pivotally connected to the pressurebar 46 to extend generally horizontally laterally to move in parallelpivotal directions as shown by arrow 56. Each rocker arm 54 moves incooperation with a earn 30 operational engaged with the cam, and areconnected to a power rod assembly 58. Each rocker arm 54 is of the sameshape and may comprise a lower surface having a curved projection 60which rides on the cam 30 and follows the cam through the edgevariations described above. The outward portion 61 of the rocker arm iscurved slightly downwardly so that the power rod assembly 58 joins therocker arm at a portion thereof which is downwardly offset from theprojection 60. A cavity portion 62 extends through the outward portion61 of the rocker arm 54 to slidably receive a shaft 64 of the power rodassembly 58. A pin 66 pivotally supports and drivably engages a springcup pivot 68 of the power rod assembly.

The power rod assembly 58 transmits reciprocal movement of itsassociated rocker arm 54 to a corresponding crank portion 22 (FIG. 1) ofthe crank shaft 20 and supplements this motion through expansion of aspring member 72.

Turning to FIG. 3, each power unit assembly 58 comprises an upper nosepiece 70, a coil spring 72, the shaft 64, and a spring cup pivot 68. Theupper nose piece 70 is rotatably fixed to its associated cross piece 22on the crank shaft 20 and terminates downwardly in rim portioncomprising a spring receiving aperture 69 and tow connecting rodapertures 71 to receive connecting rods 73. The coil spring 72 surroundsthe shaft 64 and downwardly engages the spring cup 68. The shaft 64 isfixed to the nose piece 70 and extends to the spring cup 68 supported onthe rocker arm 54. The spring cup 68 is pivotally supported on an uppersurface of the rocker arm 54 and comprises an aperture to receive alower coil of the coil spring 72. The power unit assembly 58 thusprovides compressible, expansible connecting means translating thereciprocal pivotal movement of the rocker arm 54 brought about by thecam 30 into rotation of the crank shaft 20 accompanied by compressionand expansion of the coil 72. Compression and expansion of the coilspring 72 takes place as the spring cup 68 rides on the rocker arm 54and slides along the shaft 64 towards the nose piece 70.

The relationship between the various crank portions, cams, and springsis shown in the following table:

Connecting Crank Unit Composition Shaft Cam Spring Tension Number 0Farthest Maximum Idle 1 180 Farthest Intermediate Idle 2 270 Closest 0Compressed 3 90 Farthest 0 Idle 4 315 Closest Minimum 506 Compressed 5135 Farthest Intermediate Idle 6 45 0 Maximum Idle 7 225 0 0 50%Compressed 8The above crank shaft positions are those which each individual crankportion goes through during a complete revolution and also those of eachmember at a given moment.

Returning to FIG. 1, the hydraulic a pump 12 is used to assist thethrottle assembly 14. The throttle assembly 14 comprises two hydraulicfluid reservoirs, a power assist reservoir 80 and a master reservoir 82.The master reservoir 82 is the main reservoir and controls the amount ofhydraulic pressure from pump 78 delivered through lines 84 to the tubeportions 49, 51 and 53 of the rocker arm assembly 58. A source ofelectric energy 74 controlled by a switch 76 drives an electric pump 78which develops pressure in the master reservoir 82. Pressure in the tubeportions 49, 51 and 53 forces the rocker arm rods 48, 50 and 52downward, pivoting the rest position of the rocker arms toward the crankshaft 20. Springs 86 in each tube 49, 51 and 53 help to force the rods48, 50 and 52 downward to a rest position. Pressure in the tubes 49, 51and 53 is increased through a sliding piston 87 in the master reservoir82. The force from the pump 78 initiates and facilitates movement of thepiston 87 to decrease reservoir area and increase pressure in the tubes49, 51 and 53. The piston 87 is reciprocally movable through a shaft 88connected to a second piston 90 in the power assist reservoir 80. Thesecond piston 90 also moves forward to displace the first piston 87 toincrease pressure in the tubes 49, 51 and 53. Pressure from thehydraulic pump 12 is delivered through lines 92, 94 to a first chamberportion 96 of the power assist reservoir 80 and a second chamber portion98, containing the piston 90, of the power assist reservoir. Flowthrough the first chamber portion is controlled by a sliding plate 102.The sliding plate 102 is connected to a piston 104 in the first chamberportion 96 and controlled by a rod 106. Movement of rod 106 increasespressurized fluid flow to the second chamber portion 98 to move thepiston 90 forward. The pump 12 is driven by a belt 108 from the camshaft 8 so that increased motor rpm provides increased pressure formoving the pressure bar. The amount of this pressure delivered to thepiston 90 is controlled by the plate 102. For maximum power output fromthe present apparatus, increased pressure is delivered to the pressurebas as cam shaft rpm increases. This pressure may be throttled back bymovement of the plate 104 to cut off pressure to the piston 90.

The present apparatus may further comprise an oiling system. An oil hose112 is connected to each one of the connecting shafts 64. Each shaft 64has an oil channel running through the center of the shaft full lengthto two holes 114, 116, at the top of the nose piece 70. The hose 112which is attached to the end of the connecting shaft 64 is alsoconnected to a main oil line that is connected to an oil pump 118 drivenby the cam shaft 8 through the use of a gear.

When oil is pumped up through the connecting shaft it oils bearings oneach one of the crank shaft throws. It also oils and keeps the coilsprings from getting hot and losing their tension. This is done byforcing the oil out through the two oil holes 114, 116 at the top of thenose piece 70 into a reservoir. This reservoir is created by the uses ofa rubber shelf in the nose piece 70 that is clipped to the nose piece ofthe connecting rod and also clipped to a conventional spring cup and byforming a reservoir.

The rubber shelf has holes in it about ⅔ of the way up from the bottomof the shelf, allowing the oil to be forced out when the coil spring isbeing compressed and by doing this it stops the rubber shelf fromballooning. On the power stroke the cooled oil is forced back into thereservoir because the coil spring is being expanded allowing the oil tofill up the reservoir and cooling off the coil spring. The main bearingsare oiled similarly. There are oil ports drilled in each one of thesupports and an oil hose is connected to each one.

Various modifications can be made in the design and operation of thepresent invention without departing from the spirit thereof. Thus, whilethe principal preferred construction and modes of operation of theinvention have been explained in what is now considered to represent itsbest embodiments, which have been illustrated and described, it shouldbe understood that the invention may be practiced otherwise than asspecifically illustrated and described.

1. An energy efficient motor system comprising: a rotatable cam shaft; aplurality of cam members axially spaced along a length of the cam shaftand fixed to the cam shaft for rotation therewith; wherein each of thecam members comprises an edge varying in distance from a center ofrotation of the cam member between a maximum distance and a minimumdistance; a plurality of rocker arms, one following each of said cams,pivotally attached at a first end to a hydraulic energy input andconnected at a second end to an expandable, compressible power unitassembly; and a crank shaft having a crank portion for connection witheach power unit assembly, rotatably drivable application of a force onthe first and of at least one rocker arm by rotation of said cam shaftand reciprocal movement of said power unit assembly.
 2. The motor systemof claim 1 wherein said edge of each cam member is at a maximum distancefrom the cam shaft through approximately 90° of rotation and at aminimum distance from the cam shaft through approximately 135° ofrotation.
 3. The motor system of claim 2 wherein each of the power unitassemblies are connected to the crankshaft at a degree of rotation ofthe crankshaft whereas a crank portion rotates away from the cam memberwhile the cam member is at the maximum distance from the cam shaft. 4.The motor system of claim 1 further comprising: a pressure baroperatively connected to each of the first ends of the rocker arms andvariably positionable relative to the cam members for controllingcompression applied to said power unit assembly.
 5. The motor system ofclaim 4 wherein the hydraulic energy input comprises a hydraulic pumpoperably connected to the crank shaft for applying hydraulic pumpoperably connected to the crank shaft for applying hydraulic pressure toposition the pressure bar.
 6. The motor system of claim 5 furthercomprising: a throttle means for controlling a flow of hydraulic fluidto variably position the pressure bar.
 7. The motor system of claim 5further comprising: an electric pump for applying hydraulic pressure toposition the pressure bar.
 8. The motor system of claim 1 wherein thepower unit assembly comprises a spring cup pivot operably connected tothe cam shaft, a nose piece operably connected to the crank shaft, acentral shaft connected to the nose piece and slidably receivable by thespring cup pivot, and a spring supported within the spring cup pivot andadapted to encourage separation of the nose piece and the spring cuppivot during operation of the motor.